Tabriz is the fifth most populated city in Iran, one of the historical capitals of Azerbaijan and the present capital of East Azerbaijan Province. It is situated in the valley of the Quru River and its elevation from sea level is about 1,350 meters. Tabriz is located in a valley to the north of the long ridge of the volcanic cone of Sahand, south of the Eynali mountain. The valley opens out into a plain that slopes gently down to the north eastern end of Lake Urmia, 60 kilometres (37 miles) to the west. With cold winters and temperate summers the city is considered a summer resort. The estimated population of the city is around 3,050,241 based on results of the Iranian census bureau. Tabriz is the forth most populous city in Iran after Tehran, Mashhad, and Isfahan. Tabriz is a major hub for heavy industries including automobile, machine tools, oil and petrochemical and cement production. Tabriz is famous within Iran as the holder of many historical, economical cultural achievements. These include such titles as the "City of Firsts",the city without beggars and homelessness, the city of underpasses and overpasses, the safest city in Iran (crime rate is the lowest in Iran), Iran's healthiest city, the cradle of Iran's foreign investments, the second industrial city of Iran, Iran's automotive hub for parts, car manufacturing and the biggest engine producer in the middle east, the chocolate city of Iran, the second university city of Iran, the second city for tower construction in Iran, the second pole of medical sciences in Iran, the second largest city in attracting health tourists in Iran, and one of the most important host cities in Iran. With a rich history, Tabriz contains many historical monuments, but repeated devastating earthquakes and several invasions during frequent wars have substantially damaged many of them. Many monuments in the city date back to the Ilkhanid, Safavid, and Qajar periods, among them is the large Tabriz Historic Bazaar Complex which is inscribed as a World Heritage Site in 2010. The oldest signs of the civilization in the city is an excavation site and museum in the city center with a history that dates back 2500 years.